Message from the President of the United State

UANL

First Example of Organocatalysis by Polystyrene-Supported PAMAM Dendrimers: Highly Efficient and Reusable Catalyst for Knoevenagel Condensations

This paper describes the first use of polystyrene-supported poly(amidoamine) (PAMAM) dendrimers as heterogeneous basic organocatalysts for carbon–carbon bond formation. Polystyrene-supported PAMAM dendrimers of first, second and third generations have been used as reusable base catalysts in Knoevenagel condensations of carbonyl compounds with active methylene compounds. The reactions proceed in short periods of time and with 100% selectivity. This novel catalyst eliminates the use of aromatic and halogenated solvents, as well as complex purification processes. The catalysts can be recycled ten times.

First results of experimental and theoretical investigations on sextet states of doubly-excited five-electron ions

In continuation of our previous work on doubly-excited ions with three and four electrons we present the first results on optical transitions in the term system of doubly-excited ions with five electrons. Transitions between such sextet states were identified in beam-foil spectra of the ions nitrogen, oxygen and fluorine. Assignments were first established by comparison with Multi-Configuration Dirac-Fock calculations. Later assignments were aided by Multi-Configuration Hartree-Fock calculations (see the contribution by G. Miecznik et al. in this issue). Decay curves were recorded for all six candidate lines. The lifetime results are compared to theoretical values which confirm most of the assignments qualitatively.

Development and/or change of the notion of permanent object and operative causality: empirical evidence in the first year of life

This study examines the notion of permanent object during the first year of life, taking into account the controversy of two approaches about the nature of change: developmental change and cognitive change. Using a longitudinal/cross-sectional design, tasks adapted of the subscale of permanent object and operative causality of the Uzgiris-Hunt Scale (Uzgiris and Hunt, 1975) (Uzgiris & Hunt, 1975) were presented to 110 infants of 0, 3, 6 and 9 months-old, which reside in three cities of Colombia. The results showed three types of strategies: (a) Not resolution; (b) Exploratory and (c) Resolution, which follow different trajectories in children’s performance. This allows affirming that adaptive conquests of the cognitive development stay together with the variety of strategies. Using strategies reveals adjustments and transformations of action programs that consolidate the notion of permanent object not necessarily with age, but with self-regulatory processes. Empirical evidence contributes to the understanding of the relations between the emergence of novelty in the development and performance variability

Informal housing in the XXI century. Characteristics of the informal land and housing supply in Bogota during the first decade of the XXI century

This article characterizes the conditions of the informal land and housing supply during the first decade of the xxi century in Bogota, regarding magnitude and location of the informal urban growth (new occupations in the periphery and informal densification of consolidated areas), housing  conditions in recent occupations and the characteristics of the land market. The situation of the  last decade has been reconstructed based in aerial photography analysis, census data quantification  and data analysis from planning and control public entities. Results suggest that due to the relative  land scarcity in Bogotá, among other aspects, the informal market dynamics have experimented changes compared to previous decades, because the growth in consolidated urban areas becomes  more important than the informal urbanization of the peripheries, but at the same time informality  transcends the municipal perimeter to the neighboring municipalities.

Extra activities for the English class in the first cycle of Primary School. 'Actividades extra para la clase de inglés del primer ciclo de Educación Primaria'.

Resumen basado en el de los autores. Trabajo al que se le concedió una ayuda para la creación de materiales curriculares interactivos en el año 2003

Oxford first book of space.

Este recorrido por el universo, lleva a los niños a un viaje alrededor de los planetas, las estrellas, y el más allá. Se analizan los orígenes y la naturaleza de los distintos cuerpos celestes, se explican fenómenos como el agujero negro y los eclipses solares, se repasa la historia de la exploración espacial, y se pondera la posibilidad de vida más allá de la Tierra. Se fomenta la participación en actividades interactivas.

Oxford first book of science.

La primera guía de la ciencia para los niños de seis a ocho años debe abrir sus mentes a ésta y hacerles comprender que es todo lo que hay a su alrededor. Para ello ,se presentan y explican los temas de la ciencia, referidos siempre a experiencias cotidianas que conoce bien el niño. Así, se captura su interés e imaginación, y también, es una forma de dar respuestas para la realización de sus trabajos escolares.

The Usborne first book of art.

Este título está diseñado para introducir, con un ambiente divertido, a los niños en obras de arte y artistas famosos. Así podrán hacer sus propias versiones, basadas en ideas y métodos similares.

Electronic and vibrational contributions to first hyperpolarizability of donor-acceptor-substituted azobenzene

In this study we report on the electronic and vibrational (hyper)polarizabilities of donor–acceptorsubstituted azobenzene. It is observed that both electronic and vibrational contributions to the electric dipole first hyperpolarizability of investigated photoactive molecule substantially depend on the conformation. The contributions to the nuclear relaxation first hyperpolarizability are found to be quite important in the case of two considered isomers (cis and trans). Although the double-harmonic term is found to be the largest in terms of magnitude, it is shown that the total value of the nuclear relaxation contribution to vibrational first hyperpolarizability is a result of subtle interplay of higher-order contributions. As a part of the study, we also assess the performance of long-range-corrected density functional theory in determining vibrational contributions to electric dipole (hyper)polarizabilities. In most cases, the applied long-range-corrected exchange correlation potentials amend the drawbacks of their conventional counterparts